Put me in the less than satisfied catagory, so far.
1) The Best Rate discount is only available on line. I could live with "on line" but I have constant issues accessing DisneyWorld on line. I use a Mac, latest equipment and OS, Safari and Explorer (latest versions). I get system error messages 90% of the time. Way too much work.
2) Aside from the technical issues, I have a problem with implementation of this program. When we go to WDW, my family of 4 books two rooms (one for myself and wife, one for daughters). Under the new program, I have to reserve one room with a deposit, then sign in again (I don't even know if I can do this with my pass or I have to set up a separate account for my wife with her annual pass) and look for a second room at the same hotel. If I find one, I then have to book it with a deposit. THEN, I must call reservations, get the names rearranged, request adjoining rooms. Oh, AND, the discount may be different at each hotel, and the only way to find out is to check availability one hotel at a time (normally we would just know x$ per day off rack rate at a deluxe, y$ at moderate, etc.
3) Finally, what does "Best" mean? I called the AP hotline number from the website, and when I keyed the "info on benefits" option, I got normal reservations. They told me that you were guaranteed the best AP rate when you made the reservations, but should it subsequently drop, you would not benefit unless you called to change rates.

When I queried this, I was transferred elsewhere at guest services where the CM told me that if there were a later, better, offer to APHs at the hotel, we would get that benefit. I am still unclear what happens if a lower rate is offered (rack) at a later date.
To be fair, both CMs were polite. I thought, however, that the Guest Services CM was exasperated with the questions. He needed to put me on hold to get answers.
I have always been perfectly happy making reservations on the phone. I am what other posters have called happy and satisfied. Also, as someone booking two off season rooms, for our third trip this year, I am a good customer. But I am not happy with this program.
AP benefits make economic sense to Disney. Everybody has frequent discounts. With all due respect, the "delux" hotels are not low priced relative to similar hotels (at the AP price). I don't know why this new program requires so much jumping through hoops.
I may just email Disney myself, but I wanted drusso to know he/she isn't the only one with issues with Best Rate. I apologize for the long post, but I wanted to be clear.